Greenhouse

[@Mountainman6114]

Hello there,
I’m looking for some advice on over wintering my trees in my greenhouse. I’m in zone 6 US.
My greenhouse is not heated and winter here normally doesn’t get below 5. I don’t know how often I should water my confers, I have been watering them once every two or three weeks. Well long story short, I have lost 3 Japanese white pine 2 black pine 2 Virginia pine and a yew. Bummer to say the least. I have pretty much came to the conclusion I drowned them. Any thoughts?

 

[Desert O'Piñon]

A lot of factors can affect the moisture needs of your trees. Soil type, temperature, humidity, airflow, light, etc. If you have a dense organic soil, it will hold a lot of water for a longer time than a standard inorganic coarse bonsai soil/substrate. So, the easy answer is: it depends. This is definitely the most common answer for most bonsai questions.
If you add your general location to your profile, it will produce better answers, as people will be able to know your local climate in order to give you the best advice.
Welcome to the community!

 

[JudyB]

Could be overwater or under, no way to help tell what it was without more info. Esp. Substrate info.

 

[@Mountainman6114]

Organic soil mostly, pine bark, compost, lava rock, pumice. Most of my trees are in pots and in early development, I lost two trees in bonsai pots. I’m 90% sure it’s death by overwatering. However not all of my trees have died. So that’s a good sign.

 

[WNC Bonsai]

I have JBP, juniper, Sekka hinoki, bald cypress, Blue Atlas cedar in my greenhouse (zone 7a) but I keep it above 34 degrees. So I water them all whenever the soil starts to dry out. However my soil is mostly inorganic with 10-20% pine bark, so it drains freely. So far they all look very healthy and some have even started to pop buds.

 

[JudyB]

Perhaps you could stick a wooden skewer into the rootball so you can check with more accuracy how moist your soil is staying lower in the soil. If you transition to a freer draining material this repotting season, that may help you with your winter season. It will of course need a lot more watching for drying out in the growing season. Glad there are some that made it so far!